1. Field of the Invention
The present invention relates to a mobile machine for leveling, lining and tamping a track, which comprises an elongated machine frame supported on undercarriages for continuous movement along the track in an operating direction during a leveling, lining and tamping operation, the machine frame comprising three machine frame parts arranged successively adjacent each other in a direction of elongation of the machine frame and pivotally linked to each other, a carrier frame supported on at least one undercarriage for intermittent movement along the track relative to the continuously moving machine frame and one machine frame part bridging over the carrier frame, and a track tamping unit and a track lifting and lining unit mounted on the carrier frame.
2. Description of the Prior Art
A machine of this type has been described in an article in "Der Eisenbahningenieur", January 1991, pages 24/25 (FIG. 5), where it has been designated as machine AC-109 FRP. In this machine, the intermediate machine frame part arranged between the front and rear machine frame parts is supported at its opposite ends by swivel trucks and these front and rear machine frame parts are trailers, one of whose ends is linked to the ends of the intermediate machine frame part while their opposite ends are supported on undercarriages- The front trailer is equipped with a ballast plow arrangement and operating controls while the rear trailer carries a ballast broom arrangement. A carrier frame is arranged below the bridge-like intermediate machine frame part between the swivel trucks, and its rear end is supported on the track by an undercarriage. A vertically adjustable tamping unit arranged for the simultaneous tamping of two ties and a track lifting and lining unit are mounted on the carrier frame. A front end of the carrier frame is linked to the intermediate machine frame part and connected thereto by a displacement drive for displacing the carrier frame in the direction of elongation of the machine frame. This enables the so-called tamping satellite to be intermittently displaced during the tamping operation while the machine frame advances continuously along the track. This machine can be used only in tangent track but not in switches.
Another type of a continuous action tamping machine has been disclosed in U.S. Pat. No. 4,630,541. This machine has an elongated, bridge-like machine frame whose opposite ends are supported on the track by swivel trucks. A carrier frame is linked to the elongated machine frame between the swivel trucks as a satellite carriage and is supported on the track by two undercarriages. A coupling constituted by a hydraulic longitudinal displacement drive connects the satellite carriage to the machine frame. The carrier frame carries only the tamping unit and track lifting and lining unit while the operator's cabs, the power plant and controls are arranged on the continuously advancing machine frame to reduce the weight of the intermittently moving satellite carriage.
U.S. Pat. No. 5,101,733 discloses a ballast tamping machine comprising a two-part machine frame whose two parts are pivotally linked to each other and which is supported on the track by three undercarriages- A tamping unit and a track lifting and lining unit precede the intermediate undercarriage in the operating direction and are arranged within view of an operator's cab. A ballast plow arrangement and a broom arrangement are mounted on the machine frame rearwardly of the intermediate undercarriage. A ballast conveyor arrangement extending in the direction of elongation of the machine frame has an inlet end receiving excess ballast swept up by the broom arrangement and a discharge end discharging the excess ballast into a storage bin. The storage bin is connected to a ballast discharge device with discharge openings adjacent the tamping unit to deliver ballast into cribs in track sections which do not have enough ballast for effective tamping. The discharge openings are remote-controlled from the operator's cab.